This is the HC-SR04 ultrasonic ranging sensor. This economical sensor provides 2cm to 400cm of non-contact measurement functionality with a ranging accuracy that can reach up to 3mm. Each HC-SR04 module includes an ultrasonic transmitter, a receiver and a control circuit.
- Working voltage : 5V(DC);
- Static current: Less than 2mA;
- Output signal: Electric frequency signal, high level 5V, low level 0V;
- Sensor angle: Not more than 15 degrees;
- Detection distance: 2cm~450cm;
- High precision: Up to 3mm;
- Mode of connection: VCC / trig(T) / echo(R) / GND.
- Adopt IO trigger through supplying at least 10us sequence of high level signal;
- The module automatically send eight 40khz square wave and automatically detect whether receive the returning pulse signal;
- If there is signals returning, through outputting high level and the time of high level continuing is the time of that from the ultrasonic transmitting to receiving.